The U-NUT® self-locking nut has an integrated A2 stainless steel lock ring. This lock ring functions as a spring on the thread flanks during and after assembly and exerts a clamping force of the nut on the thread.
Thus, the resulting friction torque generated in reaction to the pitch and reactive force is greater than the loosening torque that occurs in use. This results in a friction lock that effectively secures the bolted connection, even at high vibration.
The U-NUT® is used wherever failure of the screw connection would be critical or where screw-locking is always required. The versatility of the U-NUT® makes it suitable for either conventional bolted joints in accordance with VDI 2230, or applications with shorter clamping lengths and unclear fastening parameters.
The lock ring guarantees a secure connection capable of passing the NAS 3350 American National Aerospace Standard test.